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Jacques Belaiche

Publications and source records attributed to Jacques Belaiche.

11 recordsLinked to original sources
PubMed2006

No association between C-reactive protein gene polymorphisms and decrease of C-reactive protein serum concentration after infliximab treatment in Crohn's disease.

We recently showed an association between the FCGR3A V/F polymorphism and the biological response [assessed on the basis of a C-reactive protein (CRP) concentration decrease] to infliximab in Crohn's disease. The CRP and FCGR3A genes are located on the same 1q23 locus. The present study aimed: (i) to exclude a linkage disequilibrium (LD) between the two genes and (ii) to study the association between CRP polymorphisms and the response to infliximab, particularly the decrease in CRP after treatment, in Crohn's disease patients. FCGR3A (V/F) polymorphism and three CRP polymorphisms (-717G/A, 1444C/T, CRP 4A/G) were determined in 206 healthy blood donors and 189 Crohn's disease patients who had received infliximab for either refractory luminal or fistulizing Crohn's disease. Clinical response was defined as complete, partial or absent according to the same definition as in controlled trials. The biological response was defined on the basis of CRP decrease. There was no LD between CRP and FCGR3A in healthy donors or Crohn's disease patients. CRP polymorphisms had no impact on CRP decrease after infliximab. The proportions of Crohn's disease having a positive clinical or biological response were not statistically different among the various genotypes of CRP polymorphisms. There was no LD between CRP and FCGR3A polymorphisms. CRP polymorphisms were not associated with the response to infliximab in Crohn's disease.

Adolescent↗
PubMed2006

Lymphotoxin alpha gene in Crohn's disease patients: absence of implication in the response to infliximab in a large cohort study.

A haplotype in the lymphotoxin alpha (LTA) gene has been associated with a lack of response to infliximab in a small cohort of Crohn's disease (CD) patients. The present study aimed to confirm the implication of this haplotype in the response to infliximab in a larger cohort of Caucasian patients. The response to the first infusion with infliximab was evaluated in 214 Caucasian patients with either luminal (n=150) or fistulising (n=64) CD. Clinical response was based on the decrease in CD Activity Index (luminal) or on the evolution in the fistula discharge (fistulising). Biological response was assessed in 139 patients who had elevated C-reactive protein (CRP) before treatment and for whom CRP values were also available after treatment. A positive biological response was defined as a decrease in CRP of at least 25%. The patients were genotyped for six polymorphisms in the LTA gene. A positive clinical response was present in 65.4% of the patients and a positive biological response was observed in 80.6% of the patients. No association was found with any of the studied polymorphisms, nor with the previously published LTA haplotype and the response to infliximab. We could not confirm an association between the LTA locus and clinical or biological response to infliximab in a large cohort of CD patients.

Adult↗
PubMed2006

The TNF/ADAM 17 system: implication of an ADAM 17 haplotype in the clinical response to infliximab in Crohn's disease.

Infliximab, a chimeric anti-tumour necrosis factor (TNF)-alpha antibody induces a clinical response in 70% of Crohn's disease patients and the response to infliximab therapy could be partially determined by genetic factors. The implication of both transmembrane and soluble forms of the TNF-alpha in the mechanism of action of infliximab has been demonstrated. The aim of our work was first to perform a complete study of TNF variants role in the response to infliximab in Crohn's disease. Secondly, considering the role of ADAM 17 in TNF-alpha shedding, the ADAM 17 locus was also studied. The response to infliximab was evaluated in 222 Caucasian Crohn's disease patients with a luminal (n=160) or fistulizing (n=62) form of the disease. Clinical and biological response evaluation was based on the Crohn's Disease Activity Index score and C-reactive protein level evolutions, respectively. The entire TNF gene was sequenced on the complete cohort. Twelve single nucleotide polymorphisms spanning the ADAM 17 locus were studied and haplotypes rebuilt. A clinical response was observed in 64% of the patients and biological response in 77.1% of patients. No association was found between the TNF gene and the response to infliximab. One haplotype in the ADAM 17 region was associated with a clinical response to infliximab in CD patients (adjusted P=0.045). In conclusion, our results exclude, with a reasonable power, an implication of the TNF gene in the response to infliximab in Crohn's disease, but reveal a potential role of the ADAM 17 gene in this response.

ADAM Proteins↗
PubMed2005

Hepatitis C virus genotype 5 in southern belgium: epidemiological characteristics and response to therapy.

Data are scarce on patients infected with hepatitis C virus of genotype 5, due to the low prevalence of this genotype around the world. To better define the characteristics of these patients, we reviewed the files of 16 genotype 5 patients. Mean age was 38 +/- 14. All patients were of European origin. Most of them (75%) had been contaminated by transfusion within a short time period (between 1980 and 1991). There were no intravenous drug addicts. Seven patients received treatment. One patient did not respond to interferon (IFN) monotherapy. Of four patients treated with IFN and ribavirin, three became sustained viral responders. Two patients treated with pegylated IFN and ribavirin became sustained viral responders. In our region, genotype 5 patients seem to have been contaminated within a relatively short time period. Treatment with IFN or pegylated IFN and ribavirin gave a high rate (83%) of sustained viral responses.

Adult↗
PubMed2003

Optimizing treatment with thioguanine derivatives in inflammatory bowel disease.

Thioguanine derivatives, azathioprine and 6-mercaptopurine, represent major drugs in the treatment of chronic active inflammatory bowel disease. They are effective in two-thirds of the patients and safe over the long term in patients who can tolerate them (80-90%). Recent progress in understanding the metabolism of these drugs and its implication in clinical practice have brought up new tools and strategies that are proposed to optimize treatment. In particular, the measurement and characterization of key enzymes and metabolites may have clinical impact. Thus, thiopurine methyl transferase genotyping and activity measurement, as well as erythrocytes, 6-thioguanine nucleotides and 6-methyl mercaptopurine levels, may help in some situations of intolerance or inefficacy with these drugs. Indications for starting and stopping treatment with thioguanine derivatives are also discussed.

Azathioprine↗
PubMed2002

CARD15/NOD2 mutational analysis and genotype-phenotype correlation in 612 patients with inflammatory bowel disease.

CARD15/NOD2 encodes a protein involved in bacterial recognition by monocytes. Mutations in CARD15 have recently been found in patients with Crohn disease (CD), a chronic inflammatory condition of the digestive tract. Here, we report the mutational analyses of CARD15 in 453 patients with CD, including 166 sporadic and 287 familial cases, 159 patients with ulcerative colitis (UC), and 103 healthy control subjects. Of 67 sequence variations identified, 9 had an allele frequency >5% in patients with CD. Six of them were considered to be polymorphisms, and three (R702W, G908R, and 1007fs) were confirmed to be independently associated with susceptibility to CD. Also considered as potential disease-causing mutations (DCMs) were 27 rare additional mutations. The three main variants (R702W, G908R, and 1007fs) represented 32%, 18%, and 31%, respectively, of the total CD mutations, whereas the total of the 27 rare mutations represented 19% of DCMs. Altogether, 93% of the mutations were located in the distal third of the gene. No mutations were found to be associated with UC. In contrast, 50% of patients with CD carried at least one DCM, including 17% who had a double mutation. This observation confirmed the gene-dosage effect in CD. The patients with double-dose mutations were characterized by a younger age at onset (16.9 years vs. 19.8 years; P=.01), a more frequent stricturing phenotype (53% vs. 28%; P=.00003; odds ratio 2.92), and a less frequent colonic involvement (43% vs. 62%; P=.003; odds ratio 0.44) than were seen in those patients who had no mutation. The severity of the disease and extraintestinal manifestations were not different for any of the CARD15 genotypes. The proportion of familial and sporadic cases and the proportion of patients with smoking habits were similar in the groups of patients with CD with or without mutation. These findings provide tools for a DNA-based test of susceptibility and for genetic counseling in inflammatory bowel disease.

Adolescent↗
PubMed2002

NOD2/CARD15 does not influence response to infliximab in Crohn's disease.

BACKGROUND & AIMS: NOD2/CARD15 was recently identified as the first gene underlying Crohn's disease (CD) susceptibility. Monoclonal antibodies to tumor necrosis factor (TNF)-alpha (infliximab) are a potent treatment for CD, with about 70% of patients responding. It is not clear which factors influence treatment outcome. We assessed whether variants in NOD2/CARD15 are predictive for differences in clinical response. METHODS: Two hundred forty-five CD patients (86 fistulizing, 159 luminal) receiving infliximab in an expanded access program were genotyped for the 3 main associated variants of NOD2/CARD15, without knowledge of the treatment response. Short-term clinical response was assessed at 4 weeks (refractory) or 10 weeks (fistulizing) after first infliximab infusion, and the mean duration of response was calculated. In a subgroup of patients, production of TNF in response to lipopolysaccharide (LPS) in mucosal biopsy tissue was also determined by means of immunoassay, and results were related to the different NOD2/CARD15 genotypes. RESULTS: In total, 32.6% of patients carried mutations in NOD2/CARD15 (18.8% R702W, 8.6% G908R, and 10.2% 1007fs) compared with 15% in controls (P < 0.001). Despite observed differences in TNF production in mucosal biopsy tissue, there was no relationship between the overall presence of a mutation in NOD2/CARD15 or of any of the mutations separately and short-term infliximab response or response duration. Furthermore, multivariate analysis could not identify clinical characteristics that, in combination with NOD2/CARD15 mutations, were associated with response to infliximab. CONCLUSIONS: In this cohort of CD patients, the frequency of NOD2/CARD15 mutations was significantly greater than that of healthy controls. However, NOD2/CARD15 was not predictive of treatment outcome with infliximab in CD.

Adult↗
PubMed2002

Demographic and clinical parameters influencing the short-term outcome of anti-tumor necrosis factor (infliximab) treatment in Crohn's disease.

OBJECTIVE: Infliximab is an effective treatment for refractory or fistulizing Crohn's disease (CD). However, about 30% of patients do not respond to infliximab for unknown reasons. Identifying predictive factors of response is important for optimizing clinical management and for better understanding infliximab's mechanisms of action. The aim of this study was to assess whether demographic or clinical parameters influence short-term response to infliximab. METHODS: The first 240 CD patients of the Belgian Infliximab Expanded Access Program were studied for response to infliximab treatment and assessed at 4 (refractory luminal CD) or 10 wk (fistulizing CD) after the first infusion. Detailed demographic and clinical information on age, sex, type of disease (fistulizing or refractory), Crohn's Disease Activity Index score, C-reactive protein (CRP), smoking habits, disease duration, localization of disease, concomitant medication, and previous surgery were obtained from all patients. Logistic regression and decision tree analysis were performed. RESULTS: There were 73.5% responders and 26.5% nonresponders to treatment. Stepwise logistic regression identified age (OR = 0.971, 95% CI = 0.947-0.995, p = 0.018), isolated ileitis (OR = 0.359, 95% CI = 0.177-0.728, p = 0.004), and previous surgery (OR = 0.429, 95% CI = 0.233-0.787, p = 0.006) as inversely correlated with response, whereas isolated colitis (OR = 1.905, 95% CI = 1.010-3.597, p = 0.046) and concomitant immunosuppressive treatment (OR = 2.670, 95% CI = 1.430-5.016, p = 0.0022) were positively correlated with response to infliximab. Surprisingly, smoking habits were not retained as predictors for response. Decision tree analysis provided a working algorithm based on age and immunosuppressive treatment that warrants further exploration. CONCLUSIONS: In this large cohort of infliximab-treated CD patients, young age, Crohn's colitis, and concomitant immunosuppressive treatment were identified as independent variables favoring short-term response to infliximab.

Adult↗
PubMed2002

Epidemiology of inflammatory bowel diseases in the elderly in the province of Liège.

OBJECTIVE: Inflammatory bowel diseases (IBD) are heterogeneous diseases which affect preferentially young adults. The late onset could represent a particular form of expression of these diseases. The aim of our prospective study was to describe the incidence of IBD in patients older than 60 years as well as their clinical pattern in comparison with a population younger than 60. METHODS: A standardized questionnaire for each new case diagnosed in the province of Liège between 01/06/1993 and 31/05/1996 was completed. RESULTS: During the three years, 270 patients were enrolled. In group IBD > 60 years old, there were 60 new cases, including 23 cases with Crohn's disease (CD) (38%), 30 with ulcerative colitis (UC) (50%), and 7 with undetermined colitis (IC) (12%). The proportion of CD was significantly lower in the group IBD > 60 years old than in the group<60 (114 CD (54%), 81 UC (39%) and 15 IC (7%); P=0.04). The annual incidence tended to be higher for UC than for CD in group IBD > 60 (4.5 and 3.5 per 100,000, respectively) while it was the contrary in younger patients (3.4 and 4.8 per 100,000, respectively). There was no striking difference in the clinical features for both diseases in the two groups, except more frequent diarrhea, weight loss and extraintestinal symptoms in CD patients<60 years old. CONCLUSIONS: In the province of Liège, the incidence of IBD in people older than 60 years is high. IBD in the elderly is characterized by a lower proportion of CD than in the younger population. Clinical features tend to be the same whatever the age at diagnosis for each disease.

Age Factors↗